RESUMEN
In a previous paper (Pyska & Styczynski, 1979) it was shown that protein level in the diet of a rat influences the development of its mammary gland during the animal's growth to sexual maturity. Rats fed a semi-synthetic diet containing 15% protein had better-developed mammary glands than rats on a diet containing 10% protein. The aim of the study now reported was to investigate the effect of the protein level in the diet on the development of the mammary gland during pregnancy and 14 d of lactation.
Asunto(s)
Proteínas en la Dieta/administración & dosificación , Lactancia , Glándulas Mamarias Animales/crecimiento & desarrollo , Preñez , Ratas/fisiología , Animales , Femenino , Embarazo , Ratas/crecimiento & desarrolloAsunto(s)
Caseínas/farmacología , Glándulas Mamarias Animales/fisiología , Animales , Peso Corporal/efectos de los fármacos , ADN/metabolismo , Proteínas en la Dieta/administración & dosificación , Femenino , Tamaño de los Órganos/efectos de los fármacos , ARN/metabolismo , Ratas , Maduración SexualRESUMEN
The purpose of this work was to compare the oxytocic activity of plasma in oestrous cows during milking and for the first and second days following oestrous. Oxytocic activity of blood plasma was measured by the in vitro rat mammary cube assay of van Dongen and Hays. During oestrous, signigicantly lower amounts of oxytocin are released into the bloodstream of cows following milking as compared with the control values.